494 FALLACIES. 



as that there must be four elements, because there are four possible 

 combinations of hot and cold, wet and dry : that there must be seven 

 planets, because there were seven metals, and even because there were 

 seven days of the week. Kepler himself thought that there could be 

 only six planets because there were only five regular solids. With these 

 we may class the reasonings, so common in the speculations of the 

 ancients, founded upon a supposed perfection in nature ; meaning by 

 nature the customary order of events as they take place of themselves 

 without human interference. This also is a rude guess at an analogy 

 supposed to pervade all phenomena, however dissimilar. Since what 

 was thought to be perfection appeared to obtain in some phenomena, 

 it was inferred to obtain in all. " We always suppose that which is 

 better to take place in nature, if it be possible," says Aristotle : and 

 the vaguest and most heterogeneous qualities being confounded to- 

 gether under the notion of being better, there was no limit to the wild- 

 ness of the inferences. Thus, because the heavenly bodies were " per- 

 fect," they must move in circles, and uniformly. For " they" (the 

 Pythagoreans) "would not allow," says Geminus,* " of any such disor- 

 der among divine and eternal things, as that they should sometimes 

 move quicker and sometimes slower, and sometimes stand still ; for no 

 one would tolerate such anomaly in the movements even of a man 

 who was decent and orderly. The occasions of life, however, are 

 often reasons for men going quicker or slower, but in the incoiTupt- 

 ible nature of the stars, it is not possible that any cause can be alleged 

 of quickness or slowness." It is seeking an argument of analogy very 

 far to suppose that the stars must observe the rules of decorum in gait 

 and can'iage, prescribed for themselves by the long-bearded philos- 

 ophers satirized by Lucian. 



As late as the Copernican controversy it was ui-ged as an argument 

 in favor of the true theory of the solar system, that " it placed the fire, 

 the noblest element, in the centre of the universe."! This was a rem- 

 nant of the notion that the order of nature must be perfect, and that 

 perfection consisted in conformity to rules of precedency in dignity, 

 either real or conventional. Again, reverting to numbers : certain 

 numbers were 2^<^''fict, therefore those numbers must obtain in the 

 great phenomena of nature. Six was a perfect number, that is, equal 

 to the sum of all its factors ; an additional reason why there must be 

 exactly six planets. The Pythagoreans, on the other hand, attributed 

 perfection to the number ten ; but agreed in thinking that the perfect 

 number must be somehow realized in the heavens; and knowing only 

 of nine heavenly bodies to make up the enumeration, they asserted 

 " that there was an anticlithon or counter-earth, on the other side of the 

 sun, invisible to us."| Even Huygens was persuaded that when the 

 number of the heavenly bodies had reached twelve, it could not admit 

 of any further increase. Creative power could not go beyond that 

 sacred number. 



Some curious instances of false analogy are to be found in the argu- 

 ments of the Stoics to prove the equality of all crimes, and the equal 

 wretchedness of all who had not realized their idea of perfect virtue. 

 Cicero, towards the end of his Fourth Book De FiniUcs, states some 



* I quote from Mr. Whewell's Hist, of the Ind. Sc, I 165. 

 t Ibid., i., 365. t Ibid., 70. 



